1. Field of the Invention
The present invention relates to a method for producing an optical assembly and the optical assembly.
2. Description of the Related Art
Japanese Unexamined Patent Application Publication No. 2012-256869 (Patent Literature 1) discloses a method for integrating various photonic devices on a silicon photonics platform. This method includes the steps of providing a planarized silicon-based photonic substrate including a silicon (Si) waveguide structure, depositing a dielectric layer (such as a silicon oxide (SiO2) layer) on a top portion of the planarized silicon-based photonic substrate, selectively etching the dielectric layer, thereby exposing a portion of the silicon waveguide structure, using the silicon waveguide structure as a seed layer to selectively grow in the template a germanium (Ge) layer that extends above the dielectric layer, and planarizing the germanium layer to form a planarized germanium layer having a reduced thickness of 100 nm to 500 nm.
Japanese Unexamined Patent Application Publication No. 2012-133363 (Patent Literature 2) discloses an optical modulator and an optical transmitter including the optical modulator. The optical modulator includes a light input/output unit, an optical waveguide, and a phase shifter. The light input/output unit includes a vertical grating coupler or a slanted grating coupler. The light input/output unit receives an unmodulated input light signal, divides the input light signal into a first light signal and a second light signal, and transmits the first light signal and the second light signal to a first path and a second path of the optical waveguide, respectively. The phase shifter is positioned in at least one of the first path and the second path, modulates the phase of at least one of the first light signal that is transmitted through the first path and the second light signal that is transmitted through the second path using an electrical signal, and outputs the modulated light signal as a phase modulated signal.